Electric switchgear



Patented Dec. 1941 ELECTRIC SWITCHGEAB.

Floyd D. Johnson, Forest Hills, and Alvin W. Ogg,

Swissvale, Pa., assig'norl to Westinghouse Electric a Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application May 3, 1941, Serial No.- 391,640

7 Claims. (Cl. 200 31 Our invention relates, generally, to electric switchgear and, more particularly, to switchgear of the'drawout type.

When a circuit breaker, or similar apparatus, of the horizontal drawout type, is mounted in a gcubicle or cell, it is the usual practice to provide a. track structure which permits the switchgear unit to be rolled out of the cubicle to a position where it is readily available for inspection and maintenance. a

An object of our invention, generally stated, is to provide a track structure for a removable unit which shall be simple and eflicient in operation and which may be economically manufactured and installed.

A more specific object of ourinvention is to provide a folding track for an enclosed switchgear unit which may be utilized in arelatively small space.

Another object of our invention is to provide a folding track for a removable switchgear unit which will prevent. movement of the unit when.

the track is folded.

A further object of our invention is to provide afolding track having an unfolded length which is much greater than the folded length. Other objects of our invention will be explained fully hereinafter or will be apparent to those skilled in the art.

According to our invention, the folding portion of a collapsible track for supporting a movable unit is so constructed that one end engages a wheel on the movable unit to prevent movement of the unit when the track is folded. Conversely, the track cannot be folded unless the unit is in its normal position. Provision is made for lockgear unit l0. which may be a circuit breaker of the drawout type or other switching equipment. such as a network protector. which is mounted in a sheet metal cubicle I! having a cover or door II.

The suite-haemunit it is supported by rollers-II disposed on opposite sides of the unit to run on a folding or collapsible track It disposed ateachside of and within the housing H. "a.

x The track It at each side of the housing comprises a stationary portion ll and a folding extension portion It. The stationary portion I5 is secured at one end to an upright member ll of the housing H or tea similar frame member suitable for supporting the unitlll. A bracket I! having one end secured to the upright member l1 and the other end secured to the stationary portion i5 is provided for supporting the other end of the track.

As shown, the folding portion ii of the track is pivotally secured to the stationary portion I! by a pin 22 which passes through both portions.

The folding portion 86 is locked or held securely.

in the erect position by a bolt or pin 23 which passes through the member l6" and may be threaded into the stationary member l5. When the track is folded, the bolt 23 is removed fromthe member I5 and inserted through'the member 16 into the bracket Id. In this manner, the extension member may be securely locked in; either its erected or its folded position.

The wheels or rollers l3 are mounted on pins 24 provided in brackets 25,, one of which is disposed'at each side of the switchgear unit and secured to a panel 26 disposed at the rear of the unit. The panel 26 may be utilized to support the mechanism for the switchgear unit l0.

As shown in Fig. 2, each wheel I3 is provided with a-groove 21 which engages the extension portion ll of the track it when the unit is withdrawn from the housing II. A flange 28 is provided on each wheel to prevent it from leaving the edge of the track I6. When resting on the stationary portion I5 of the track-H, the load is carried by the outer periphery 29 of each wheel which engages the track. When the wheels are on the folding portion It, the load is carried by the root of the groove 21.

As shown in Fig. i, an upwardly projecting stop 3| is secured to the track 15 and' disposed to engaged the groove 21 in the rear wheel I3 when the unit I0 is fully inserted into the housing ll. Thus, the stop 3| prevents the wheel from leaving the edge of the track l5 by lateral movement and also limits the backward move ment of the unit [0.

In order to prevent l'om'ard movement of the unit l0 when the track I4 iscollapsed. the rear end of the folding portion 16 is provided with an urruate surface 32 having :1 radius R uhich is so proportioned relative to the normal positionof the rear roller l3 that the curved end 32 actually engages the groove 21 in the roller at a point above the normal height of the track l6.

Thus, when the track [6 is fully lowered, the

roller l3 cannot move forward because of the curved end 32 of the track 16 and it cannot move backward because of the stop 3|. Conversely, the track l6 cannot be dropped to its lowered position unless the roller is in its normal position. In this manner the unit l curely retainedfin the housing II. A- stop 33 may be seis provided at the outer end of the track I6 to prevent the unit J0 from rolling off the track, I when .the extension l6 isin' the erected position,

as shown by the dash dot lines in'Iig. 1.

From the foregoing'description; it, isapp'arent that we have provided a collapsibletrack for sup-- porting a movable unit'which-can be folded "or unfolded without lifting the unit'and which prevents movement. of the :unit when the track is;

folded. Furthermore, the unfoldedlength of the track can greatly exceed the folded length andlittle space is required for changing the track from one position to the other.

Since numerous changes may be made in the 5 above-described construction, and diflere'nt' embodiments of the invention may be made with- 1 out departing from the'spirit and scope thereof,

it is intended thatall matter contained in-the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. In switchgear apparatus, in combination, a}

movable'switchg'ear unit and a collapsible track for supporting the same, the track comprising a stationary portion and a folding portion pivotally secured to the stationary portion, said folding portion having an arcuate surfacefor engaging the movable unit to prevent movement thereof when the folding portion is in the collapsed position.

2. In switchgear apparatus, in combinatioma movable switchgear unit and a, 'collapsibletrack for supporting the same, the track comprisinga stationary portion and an extension portion piv-.

otally secured'to the stationary portion and mom able to either an erected position'or a collapsedposition, said extension .portionhaving'a rounded end'for engaging the movableunit to prevent movement thereof when the extension portion 'is' in the collapsed position 3.- In switchgear' apparatus, in

movable switchgear unit and a collapsible track for supporting the same, the track comprising a stationary portion and an extension portion piv-' otally secured to the stationary portion and mov combination,

able to either an erected position or a collapsed position, said extension portion having a round- 1 ed end forengaging the movable unit to prevent movement thereof when the extension portion is in the collapsed position, and means for locking the extension portion in the collapsed position;

, 4..In switchgear apparatus, in combination, ,a movable switchgear unitand a collapsible track for'supporting the same, the track comprising a stationary portion andan extension portion pivotally secured to the stationary portion and mov- '5; In switchgear-apparatus, in combination, v a movableswitchgear unit having supporting wheels thereon, a collapsibletrack for the wheels, said track comprising a'stationary portion and an extension portion pivotally secured to the stationary portion and movable to either an erected position or a collapsed position,- said extension portion having a rounded end for en-,

gaging a wheel on the unit to prevent movement thereof when the extension portion in the collapsed position.

.6. In switchgear apparatus, in combination, a,

.rriovable switchgear unit having supporting wheels thereon, a collapsible track for the-wheels,

said track comprising, a stationary portionand an extension portion pivotally secured to the stationary portion and movable to either an, erected position or a collapsed position, stop means on the stationary portion for engaging a wheel on "theunit, said extension portion having a roundwheels thereon,

edend for engaging said wheel to force it against said stopimeans when the extension portion is in the collapsed position. 1

I '7. In switchgear apparatus, in combination, a movable switchgear unit having supporting a collapsible track for the wheels,sald track comprising" a stationary portifon andflan extension portion pivotally secured :to the stationary portion and movablejto-either an erected position or a collapsed position, stop 'means on thev stationary portionfor engaging a wheel on the unit, said extension portion'haw inga, rounded end for engaging said wheel to force it against said stop meanswhen the extension portion is in the collapsed position, said wheel havingan outer'periphery for engaging the stationary portion of the track and a grooved .surface for engaging the extension portion.

. FLOYD D. JOHNSON.

ALVIN W. OGG. 

